1. Field of the Invention
This invention relates to a resistance generating device for a training bicycle, more particularly to a resistance generating device which imparts an increased resistance force to a wheel of a training bicycle in response to a higher rotation speed of the wheel.
2. Description of the Related Art
In U.S. Pat. No. 6,736,761 B2, entitled “Stationary Bicycle Resistance Generator,” a support unit is disposed to suspend a bicycle wheel of a stationary bicycle exerciser from a ground surface so as to permit rotation of the bicycle wheel. A resistance unit includes a friction wheel which is rotatably mounted on a rotating shaft and which frictionally engages the bicycle wheel to be rotated therewith, a magnetically attractive member which is mounted on the rotating shaft and which is disposed at a side of the friction wheel, and a plurality of magnets which surround the magnetically attractive member and which are angularly displaced from one another such that, when the bicycle wheel is rotated by means of a pedaling action to rotate the friction wheel, a magnetically induced resistance force is generated by the magnets and is imparted to the bicycle wheel for training purposes.
Although the resistance force can be varied by adjusting the distance between the magnetically attractive member and the magnets, during pedaling of the bicycle at a higher speed, an inertia and a centrifugal force resulting from the rotation of the bicycle wheel will counteract a part of the resistance force so that the resistance effect is reduced.